Method and apparatus for quick freezing



Sept. 2, 1941. w. M. ZAROTSCHENZEFF METHOD AND APPARATUS FOR QUICKFREEZING Filed Oct. 27, 1938 2 Sheets-Sheet 1 INVENTOR.

Q 1, Mam

ATTORNEY.

Patented opt. 2, 1941 his STATES PATEN 2,254,405 METHOD AND APPARATUSFOR QUICK mnszmo Wladimir M. Zarotschenzefl', Palisades, N.-J., as-

signor to National Frosted Foods, 1110., New

York, N. Y.

Application October 27, 1938, Serial N0. 237,188

4 Claims.

This invention relates to methods and appa ratus for quick freezing, andhas particular reference to quick freezing of foodstuffs, such as meat,fish, etc.

1 Science and commercial practice recognize the benefits of rapidapplication of refrigeration, particularly for freezing of edibleproducts. When flesh of fresh meat or fish is frozen rapidly, that iswithin two hours or less, the product on defrosting resembles mostclosely the original .result that slow frozen products become much lowerin quality from the consumers point of view.

Various methods and apparatus have been proposed for rapid freezing,outstanding among which are the inventions of Clarence Birdseye andMikail T. Zarotschenzeff. The former utilizes the principle of squeezinga uniform package with product to be frozen between parallel metalplates which are continuously refrigerated from within. This principlehas been further Worked out by Bicknell Hall who developedan n apparatushaving refrigerated metal plates between which product is squeezed underconsiderable pressure.

I have found that it is possible to eliminate the foregoing limitationsby providing an apparatus in which objects to be frozen are placedbetween bags made of an impervious to liquids fabric through whichcirculates --a liquid refrigerant,

the pressure of the latter causing the fabric of the bags to closelyenvelop the objects. This arrangement has an advantage in that objectsof various shapes and sizes can be efliciently subjected to the-actionof a cooling liquid, there being no necessity for separate or specialconmore fully described in the accompanying specification and drawingsin Which- Fig. l is a detail view of two cooling elements of myapparatus partly in section, supporting e I A pump I9 maintains theliquid'refrigerant in circulation through a heat exchanger 2. of ancartons or packages with objects to be frozen.

Fig. 2 is a similar view of the cooling elements used for freezingirregularlyshaped objects.

Fig. 3 is a similar view of modified elements used for cooling smallobjects. 7

4 is a similar view of another modification of the cooling elements.

Fig. 5' is an elevational View of my refrigerating machine. l

Fig. 6 is a fractional detail view of a liquid pp y system.

Fig. 7 is a sectional top plan view of my machine.

My machine consists of a plurality of cooling or refrigerating elementsshown in Figs. 1 and 2. Each element has aperforated plate I which canbe made of metal or other suitable material. The plate has flexible bags2 and 3 attached at their edges to the edges of the plate by clampingframes 4 and 5 joined together by screws or bolts 5. The plates aresupported on angle irons l mounted on vertical posts 9 with bottomflanges it (Fig. 5) mounted on a floor H of the machine. The bags arepreferably made of a fabric impregnated with a water-proofing compound.I have folmd that satisfactory results are obtained when the fabric istreated with high grade latex rubber which remains soft and -pliable atvery low temperatures. Furthermore,

rubber does not freeze to the flesh of refrigerated objects and is arelatively good heat conductor in a thin layer. Reference may be made tothe well known rubber trays used in domestic refrigerators for freezingice cubes. Such trays remain eleastic for many years, are unaffectedbylow temperatures and readily release the frozen ice cubes withoutpreliminary defrosting as is necessary with metal trays. Other kinds ofrubber may be also used, as well as synthetic elastic composition,varnishes, etc.

Such a bag may be prepared from two flat:

sheets of latex treated fabric which are held tightly together at theiredges by the frames I and 5 or the sheets may be formed as more or lessdeep bags. v.

The rack with the bags is placed in a housing I2 made of a heatinsulating material such as composition asbestos board etc. with frontdoors l3. Intake pipes ll are fitted into the bags one end extendingfrom a delivery header, pipe l5 for a'liquid refrigerant '25. Valves l6are placed inthe pipes H for controlling the flow of the refrigerant.Exhaust pipes I! connect the other ends of the bags with an exhaustsuctionheader pipe J8;

ordinary type (Fig. 6). The elements are so are distended by thepressure of the circulating liquid. By closing a valve ii, thecorresponding bag is emptied and caused to collapse so that objects'(Figs. 1 and or products 2| can be placed on the soft .bag supported bythe'plate I. The bag 3 of the next upper element may be also emptied byclosing its valve IS in order to facilitate the loading of the lowerelement with the objects or cartons 2|. Upon completion of the loading,the valves are opened causing the bags to distend and to envelop theobjects 2| with a slight pressure sufilcient to-produce a good contactof the bag with the sides of the objects, but insufflcient to cause anydamage to the objects even if they are placed in ordinary papercontainer, as may be the case with packed meat or fish fillets. Therubberized fabric of the bass is sufficiently flexible and elastic tocover and envelop various objects of an irregular shape such as poultry29, whole fish, chunks of meat etc. as shown in Fig. 2.

quired for freezing a charge of products although each element, with theexception of those located at the top and bottom of the machine,operates :together with two others which are above and below. Theelements are spaced so that the bags when filled approach closely thetop plates of the adjacent lower elements and may even almost touchthem, theupper plate 22 of one element forming a shelf. for loading itwith objects or products to be frozen. Various uses of these elements orshelves are shown in Fig. 5, as, for instance, freezing of oval objects3| such as full drawn poultry wrapped in moisture proof cellulosewrappers, pork hams 32 or similar highly irregu- A modified element isshown in Fig. 3 in which case it is formed with a solid plate 22 with abag 3 supported underneath by a frame 5 and screws 6. The intake andexhaust pipes I4 and H are respectively fitted into the plate 22.

This arrangement is especially suitablefor arti-'- cles having fiatbases such as single fiat fish like sole or a metal pan filled with fishseveral inches deep. Such metal pans are standard in practically allcold storage plants engaged in freezing fish so that this particularmodification permits the use of a standard equipment. Such metal pans 23are shown filled with fish 24 in Fig. 3. It is a common practice to havewater in the bottom of the pan so that .there is a direct heatabsorption from the fish by conduction through the metal pan and wateraround the fish while the upper sides of the fish are in direct contactwith the fabric of the bags. A very eflicient refrigeration is therebyobtained with this arrangement.

Another modification is shown in Fig. 4 in which direct expansionrefrigeration coils or pipes 26 pass through the bags being providedwith regulating valves 21, The refrigeration in this case is obtainedthrough the combination of. a primary or direct expansion refrigerantsuch as ammonia, carbon dioxide etc., passing through the pipes 26, andof a secondary refrigerant filling the bags between the metal plates 22and the fabric of the bags. The secondary refrigerant, which may besodium or calcium chloride brine, may circulate through the bags or thecirculation may be stopped by closing valves l6 and 28. The valves 28can be also used for regulating the back pressure in the bags. The coilsfor the primary refrigerant may beadded, of course, to the double bagsshown in Figs. 1 and-2.

The arrangement of various elements in the machine is shown in Fig. 5. Avent pipe 30 isv provided in order to remove or eliminate any'air in thesystem and to adjust the level of the liquid in the circulating system.

It may be noted that each element can be loaded or unloadedindependently of the others and while maintaining uninterruptedcirculation of the refrigerant through other elements which are notbeing handled. Thus the third from the top element is shown disconnectedfrom the circulation, its valve It being closed, so that its bag is madeflexible.

lar objects, packages 33 of uneven thickness, round fish 33 in openboxes or pans 35, etc. Elements with two bags may be used to advantagefor freezing small round or elongated objects such as corn on cob 3B, inorder to obtain a substantial contact over the whole surface with thefabric of the refrigerating elements. Flat fish 31 can also beconveniently and efficiently frozen between the adjacent bags 2 and 3.

If desired, the angle irons 1 may be made adjustable for varyingdistances between the elements in which case the'pipes l4 and i1 may beAdditional perforate or imperforate plates 38 can be also provided inthe bags in order to provide an additional support for the bags. a

It is understood-that this invention may be embodied in still othermodifications within its scope as set forth in the appended claims.

I claim as my invention:

1. A freezing apparatus comprising a casing and a plurality of spacedrefrigerating elements arranged therein, each of said elementsconsisting of a frameand a pair of opposed walls cooperating with theframe to provide an enclosed space in said element, means for supplyingeach of said cooling elements with a liquid refrigerant,

- and means for withdrawing the used refrigerant atures substantiallyto' the shape of the materials shown collapsed, permitting discharge orremoval.

confronting the wall.

2. a freezing apparatus comprising a casing and a plurality of spacedrefrigerating elements arranged therein, each of said elementsconsisting of a frame and a pair of opposed walls cooperating with theframe to provide an enclosed space in said element, means for supplyingeach of said cooling elements with a liquid refrigerant, and means forwithdrawing the used refrigerant therefrom, said walls being made from ahighly flexible waterproof resilient material having the characteristicof being able to conform at low temperatures substantially to the shapeof the materials confronting the wall. v

3. A freezing apparatus comprising a casing and a plurality of spacedrefrigerating elements arranged therein, each of said elementsconsisting of a frame and a pair of opposedwalls cooperating with theframe to provide an enclosed space in said element, means for supplyingeach of said cooling elements with a liquid refrigerant, means forwithdrawing the used. refrigerant therefrom, said walls being madefrom'a highly flexible waterproof resilient material having thecharacteristic of being able to conform at low temperaturessubstantially to the shapeof the materials confronting the wall, andconduits in container, means to supply a liquid refrigerant I intc thecontainer, the rigid wall being adapted to support articles to berefrigerated, the flexible wall of the next element above being adaptedto envelope the upper sides of the articles when the containers arefilled with the refrigerant.

XVLADIMIR M. ZAROTSCHENZEFF.

